The _-\s
is creating a range between the underscore and space characters. You need to either escape the -
as in _\-\s
or put it at the end:
[a-zA-Zа-яА-ЯЁё0-9_\s-]
Also beware of the а-я
range. If this is the same as the Latin 1 a
the range may not be what you expect at all.